Role of Locoregional Treatment in Vulvar Cancer With Pelvic Lymph Node Metastases: Time to Reconsider FIGO Staging?

Image-Guided Radiotherapy for Gynecologic Malignancies: What the Radiologist Needs to Know

Pelvic imaging is integral to contemporary radiotherapy (RT) management of gynecologic malignancies. For cervical, endometrial, vulvar, and vaginal cancers, three-dimensional imaging modalities aid in tumor staging and RT candidate selection and inform treatment strategy, including RT planning, execution, and posttherapy surveillance. State-of-the-art care routinely incorporates magnetic resonance (MR) imaging, 18F-fluorodeoxyglucose-PET/computed tomography (CT), and CT to guide external beam RT and brachytherapy, allowing the customization of RT plans to maximize patient outcomes and reduce treatment-related toxicities. Follow-up imaging identifies radiation-resistant and recurrent disease as well as short-term and long-term toxicities from RT.

Definitive chemoradiation or radiation therapy alone for the management of vulvar cancer

Vulvar cancer is rare, and unresectable disease provides a therapeutic conundrum. Although definitive surgery remains the mainstay for curative treatment of vulvar cancer, a minority of patients present with advanced disease for which surgical resection would be extraordinarily morbid. Pre-operative and definitive radiation with radiosensitizing systemic therapy allows such patients an opportunity for cure. In this review, we explore the origins of pre-operative radiation, current treatment standards for pre-operative and definitive chemoradiation, and future directions.

Safety and Benefit Of Sentinel Lymph Nodes Biopsy Compared to Regional Lymph Node Dissection in Primary Vulvar Cancer Patients Without Distant Metastasis and Adjacent Organ Invasion: A Retrospective Population Study

Background

The safety and benefit of sentinel lymph node biopsy (SLNB) compared with regional lymph node dissection (RLND) and no lymph nodes removed (NA) in patients with vulvar squamous cell cancer (VSCC) was not well studied.

Methods

A retrospective analysis on VSCC patients without distant metastasis and adjacent organ invasion from the Surveillance, Epidemiology, and End Results Program database between 2004 and 2016 was carried out. Within subgroups stratified by negative (LN−) or positive (LN+) regional lymph node findings, inverse probability weighting (IPW) adjusted multivariate Fine-Gray compete risk (CR) model and accelerated failure time (AFT) model was used to investigate the factors associated with and cancer-specific survival (CSS) and overall survival (OS).

Results

Of the 3,161 VSCC patients treated with surgery, 287 (9.1%) underwent SLNB, 1,716 (54.3%) underwent RLND, and 1,158 (36.6%) had no regional lymph nodes removed. As illustrated by IPW adjusted multivariate regressions, SLNB was significantly associated with prolonged CSS (LN−, adjusted sub-proportional hazard ratio [sHR] = 0.42; 95% confidence interval [CI], 0.19–0.93; P=0.032; LN+, adjusted sHR = 0.29; 95% CI, 0.16–0.54, P<0.001) and OS (LN−, adjusted time ratio [TR] = 1.38; 95% CI, 0.82–2.32; P=0.226; LN+, adjusted TR = 2.68; 95% CI, 1.73–4.14; P<0.001), although the effect of SLNB on OS was not significant within the LN− cohort. Moreover, SLNB led to improved CSS (adjusted sHR = 0.40; 95% CI, 0.23–0.70; P = 0.001) and OS (adjusted TR=1.15, 95% CI 0.76-1.73, P=0.279) compared with NA. Age was a significant prognostic factor of CSS and OS, whereas tumor size, surgery type, and invasion depth were not.

Conclusions

SLNB leads to significantly prolonged CSS and OS in VSCC surgery patients without distant metastasis and adjacent organ invasion than RLND, except for the similar OS in the LN− cohort. SLNB could be carried out preferentially for VSCC surgery patients without distant metastasis and adjacent organ invasion, irrespective of tumor size, surgery type, invasion depth, and regional lymph nodes metastasis. Further prospective clinical trials are warranted to confirm the findings of this study.

Diagnostic performance of preoperative [18F]FDG-PET/CT for lymph node staging in vulvar cancer: a large single-centre study

Purpose

This retrospective study aimed to assess the diagnostic performance of preoperative [¹⁸F]FDG-PET/CT in predicting the groin and pelvic lymph node (LN) status in a large single-centre series of vulvar cancer patients.

Methods

Between January 2013 and October 2018, among all consecutive women with proven vulvar cancer submitted to [¹⁸F]FDG-PET/CT, 160 patients were included. LNs were analysed by two qualitative methods assessing PET information (defined as visual assessment) and a combination of PET and low-dose CT information (defined as overall assessment), respectively, as well as semi-quantitative analysis (LN-SUV_max). Sensitivity, specificity, accuracy, positive and negative predictive values (PPV and NPV) in predicting the groin and pelvic LN status were calculated in the overall study population; a subset analysis of groin parameters in clinically/ultrasonography negative patients was also performed. Histopathology was the reference standard.

Results

All patients underwent vulvar and inguinofemoral LN surgery, and 35 pelvic LN surgery. Overall, 338 LN sites (296 groins and 42 pelvic sites) were histologically examined with 30.4% prevalence of metastatic groins and 28.6% for metastatic pelvic sites. In the overall study population, sensitivity (95% confidence interval, CI), specificity (95% CI), accuracy (95% CI), PPV (95% CI) and NPV (95% CI) at the groin level were 85.6% (78.3–92.8), 65.5% (59.0–72.0), 71.6% (66.5–76.8), 52.0% (44.0–60.1) and 91.2% (86.7–95.8) for visual assessment; 78.9% (70.5–87.3), 78.2% (72.5–83.8), 78.4% (73.7–83.1), 61.2% (52.3–70.1) and 89.4% (85.0–93.9) for overall assessment; and 73.3% (64.2–82.5), 85.0% (80.1–89.8), 81.4% (77.0–85.8), 68.0% (58.8–77.3) and 87.9% (83.4–92.5) for semi-quantitative analysis (SUV_max cut-off value 1.89 achieved by ROC analysis). Similar results were observed in the pelvis-based analysis.

Conclusion

In this large single-centre series of vulvar cancer patients, [¹⁸F]FDG-PET/CT showed good values of sensitivity and NPV in discriminating metastatic from non-metastatic LNs. In routine clinical practice, qualitative analysis is a reliable interpretative criterion making unnecessary commonly used semi-quantitative methods such as SUV_max.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05257-8.